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Satellite-derived soundings during a blowing dust event

Did satellite soundings provide information during the surface wind event on 1 May 2023 that lead to the closure of Interstate 55 (click here for a Google Traffic map from 6 PM on 1 May 2023!) south of Springfield IL (see this CIMSS Satellite blog post)? On 1 May, the location in question was observed... Read More

NUCAPS Soundings Availability points and Gridded NUCAPS Lapse RAte, 850-700 mb, 1800 UTC on 1 May 2023, along with soundings (Click to enlarge)

Did satellite soundings provide information during the surface wind event on 1 May 2023 that lead to the closure of Interstate 55 (click here for a Google Traffic map from 6 PM on 1 May 2023!) south of Springfield IL (see this CIMSS Satellite blog post)? On 1 May, the location in question was observed twice by NOAA-20, shortly before 1800 UTC (above) and ca. 1930 UTC (below). The low-level lapse rates from the NUCAPS soundings show the very strong lapse rates that accompany blowing dust.

NUCAPS Soundings Availability points and Gridded NUCAPS Lapse RAte, 850-700 mb, ca. 1930 UTC on 1 May 2023, along with soundings (Click to enlarge)

Gridded NUCAPS fields of low-level lapse rates are very revealing at 1933 UTC. Lapse rates from 925-850 and from 950-900 mb, shown below, suggest the steepest low-level lapse rates in the region just south of Springfield where the blowing dust occurred.

Gridded NOAA-20 NUCAPS Lapse Rates (925-850 mb and 950-900 mb), 1933 UTC on 1 May 2023 (click to enlarge)

GOES-16 data can also be used to derive lapse rates in the vertical (although ABI data gives scant information in the vertical). The animation below shows derived profiles at 4 locations in central Illinois at 1951 UTC. (GOES-16 profiles are created only in regions that are confidently clear — clouds were present over much of eastern IL on 1 May 2023 as shown in this Day Cloud Phase Distinction RGB animation from 1746 – 1921 UTC). The blowing dust was most apparent in satellite imagery between the two southern profiles. As with the NUCAPS profiles, dry-adiabatic conditions are present near the surface.

GOES-16 vertical profiles at 1951 UTC at locations as indicated (Click to enlarge)

A benefit of GOES-R profiles is that they are produced every 30 minutes. Thus, one can view how things evolve with time in a way that is far more difficult with NUCAPS profiles. The animations below shows the profiles and the northern and southern points in the above figure. Both profiles show surface warming over the 5 hours plotted — with the southern station warming a bit more — and well-mixed boundary layers.

GOES-16 Vertical Profiles at 40.27 N, 89,73 W, 1421 – 1951 UTC on 1 May 2023 (Click to enlarge)
GOES-16 Vertical Profiles at 30.30 N, 89,62 W, 1421 – 1951 UTC on 1 May 2023 (Click to enlarge)

GeoXO — the follow-on to the GOES-R satellite series — will carry a hyperspectral sounding (the GXS) that will provide much more accurate profiles than are available from GOES-R.

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Blowing dust causes multiple-vehicle accidents along I-55 in Illiniois

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) Dust RGB images (above) showed areas of blowing dust (shades of magenta/pink) that reduced visibility to near zero along Interstate 55 south of Springfield, Illinois (station identifier KSPI) on 01 May 2023 — which caused multiple-vehicle accidents that resulted in dozens of injuries and several fatalities. As a result,... Read More

GOES-16 Dust RGB images, with GOES-16 Derived Motion Winds plotted in white and 15-minute METAR surface reports plotted in yellow [click to play animated GIF | MP4]  

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) Dust RGB images (above) showed areas of blowing dust (shades of magenta/pink) that reduced visibility to near zero along Interstate 55 south of Springfield, Illinois (station identifier KSPI) on 01 May 2023 — which caused multiple-vehicle accidents that resulted in dozens of injuries and several fatalities. As a result, parts of I-55 in southern Sangamon and northern Montgomery County were closed in both directions. Surface reports showed wind gusts as high as 54 mph, with some GOES-16 Derived Motion Winds in the 35-40 knot (40-46 mph) range across the region. The source of this blowing dust was nearby agricultural fields that had recently been plowed during Spring planting activities.

In plots of rawinsonde data from Lincoln, Illinois (METAR station identifier KAAA, near the top-center of the Dust RGB images) shown below, a deep boundary layer adiabatic-to-superadiabatic temperature lapse rate was evident, which increased in maximum height from 806 hPa (1748 m) at 1200 UTC to 714 hPa (2743 m) at 0000 UTC. This steep boundary layer lapse rate aided the downward transfer of momentum, bringing the stronger 35-45 knot wind speeds that existed at higher altitudes down to the surface. During the time period between these 2 Lincoln IL rawinsonde launches, steep boundary layer lapse rates were also seen in sounding profiles derived from NOAA-20 and GOES-16 (as shown in this blog post).

Plots of rawinsonde data from Lincoln, Illinois [click to enlarge]

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Interesting SAR Wind structures over the Great Lakes

The RCM-1 satellite carrying SAR instruments overflew Lakes Superior and Erie/Ontario at 2350 30 April 2023 and 1135 UTC 1 May 2023, respectively. What kind of wind structures were observed, and how easily can one explain them? The imagery above shows a GOES-16 Visible animation from 2301 UTC on 30 April... Read More

GOES-16 Band 2 Visible Imagery (0.64 µm) from 2301 UTC 30 April – 0001 UTC 1 May 2023 (Click to enlarge)

The RCM-1 satellite carrying SAR instruments overflew Lakes Superior and Erie/Ontario at 2350 30 April 2023 and 1135 UTC 1 May 2023, respectively. What kind of wind structures were observed, and how easily can one explain them? The imagery above shows a GOES-16 Visible animation from 2301 UTC on 30 April through 0001 UTC on 1 May 2023. Higher-level clouds are overspreading central Lake Superior from the east (part of a large occluded system ove the Great Lakes), and northwesterly winds might be inferred over the lake — especially given the 0000 UTC surface analysis shown below. Note in particular the relative closeness of the two isobars extending northward from the western Upper Peninsula of Michigan!

Surface Analysis, 0000 UTC on 1 May 2023 (Click to enlarge)

SAR winds for just before 0000 UTC are shown below. Rather than one region of stronger winds associated with those more closely-packed isobars, 3 or 4 separate bands of slightly-stronger northwesterly winds (a still image is here; winds are upwards of 30 knots — yellow/green in the enhancement — vs. about 20 knots — cyan in the enhancement — in between the strongest winds) are apparent both upwind and downwind of Isle Royale! Isle Royale does have topographic features (here’s an image) — but it’s hard to relate those features to the downstream wind bands. AWIPS presentations of the wind speed does not include direction; those directions are available online however, at this website. This toggle shows both the derived wind speed and the Normalized Radar Cross Section field.

GOES-16 Visible Imagery (0.64 µm) at 2351 UTC overlain with RCM-1 SAR winds at 2348 UTC 30 April 2023 (Click to enlarge)

Twelve hours later, RCM-1 had a descending pass over the eastern Great Lakes between 1100 and 1200 UTC. GOES-16 Visible imagery from 1116 to 1136 UTC, bracketing the RCM-1 overpass, is shown below. The easterly flow on the Poleward side of the occluded low is readily apparent in the higher clouds over northern Lake Huron. Similarly, southwesterly winds are apparent over Lake Erie. Here is the 1200 UTC surface analysis.

GOES-16 Visible Imagery (0.64 µm), 1116 – 1136 UTC on 1 May 2023 (click to enlarge)

Strong southwesterly winds (around 30 knots — yellow/green in the enhancement used) are apparent over northeast Lake Erie, except for the nearshore waters off Erie County (NY) at the extreme eastern edge of Lake Erie, where winds are closer to 15 knots (dark blue/purple in the enhancement used). There is a linear low cloud feature extending west-northwestward from Chautauqua County — the westernmost county in New York). It is close to the transition zone between lighter winds upstream and stronger winds downstream. The sector with the southernmost winds is here; here‘s the view with winds primarily over Lakes Ontario and Huron.

GOES-16 VIsible imagery (0.64 µm) and derived SAR winds from RCM1, ca. 1128 UTC on 1 May 2023 (click to enlarge)

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Satellite signatures of the SpaceX ViaSat-3 Americas Mission launch

5-minute CONUS sector GOES-16 (GOES-East) images from all 16 ABI spectral bands (above) displayed the northeast-moving warm thermal signature of a SpaceX Falcon Heavy rocket booster as the ViaSat-3 Americas Mission was launched from Cape Canaveral Space Force Station in Florida at 0025 UTC on 01 May (8:25 PM EST on 30... Read More

GOES-16 images from all 16 ABI spectral bands, and a Rocket Plume RGB [click to play animated GIF | MP4]

5-minute CONUS sector GOES-16 (GOES-East) images from all 16 ABI spectral bands (above) displayed the northeast-moving warm thermal signature of a SpaceX Falcon Heavy rocket booster as the ViaSat-3 Americas Mission was launched from Cape Canaveral Space Force Station in Florida at 0025 UTC on 01 May (8:25 PM EST on 30 April 2023). The rocket launch condensation cloud was also evident in imagery from Infrared spectral bands (07-16), drifting slowly east-northward away from the launch site. One or both of these rocket launch signatures were detected by nearly all’ of the ABI spectral bands (except for Visible Band 1), as well as Plume RGB images.

A thermal signature of the rocket booster was also seen in 10-minue Full Disk sector GOES-18 (GOES-West) Nighttime Microphysics RGB images frm the CSPP GeoSphere site (below).

GOES-18 Nighttime Microphysics RGB images [click to play animated GIF | MP4]

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